What is KDE Connect?

KDE Connect is a project to communicate across all your devices. For example, with KDE Connect you can receive your phone notifications on your desktop computer, control music playing on your desktop from your phone, or use your phone as a remote control for your desktop. To achieve this, KDE Connect:

implements a secure communication protocol over the network, and allows any developer to create plugins on top of it.

Installation

You will most likely find the KDE Connect desktop component as a package in your distribution's repos. If you use a desktop environment other than KDE's Plasma, you might also want to install indicator-kdeconnect, that provides a system tray as a GUI for other desktops.

The app for Android can be found in both the Google Play Store and the free and open store F-Droid.
There was some development of an KDE Connect client app for iOS in 2014 (see source code) and supposedly a client app for Blackberry (where?).

If you use the Firefox browser, this cool extension lets you send links in the browser to the phone app.

Building KDE Connect (Desktop)

The easiest way to install KDE Connect is to run sudo make install. You can also install KDE Connect to a location of your choice, but you'll have to setup the paths etc. to make it work. Also, you'll need to run kdeconnectd manually, since DBus doesn't know about it.

Building KDE Connect (Android)

The code is at https://cgit.kde.org/kdeconnect-android.git/. Install Android Studio to build the app and install it to your phone. Using the emulator is possible, but need an advanced networking setup, or you won't be able to connect to your desktop.

Troubleshooting

I have two devices running KDE Connnect on the same network, but they can't see each other

KDE Connect uses dynamic ports in the range 1714-1764 for UDP and TCP. So if you are behind a firewall, make sure to open this port range for both TCP and UDP. Otherwise, make sure your network is not blocking UDP broadcast packets.

You can submit patches on our Phabricator. This wiki page has more details on how this process works. Should this be your first patch, it's good to know that it might take some time before your patch is reviewed (typically within a week though), and you'll probably have to make some changes a couple of times. That's not because you're new or because your code is code, that's what happens for all reviews (even for long-time contributors).